1. Field of the Invention
The present invention relates to a developing device that houses a developer such as toner, etc. Further, the present invention relates to a process cartridge and an image forming device. Further, the present invention relates to a method of manufacturing the developing device.
2. Description of the Related Art
A laser printer, for example, utilizes developer to print on a recording medium (printing paper, for example). The laser printer has a case for housing the developer. The developing device has a case main body in which an opening is formed. A developing roller is coupled, in a manner allowing rotation, to the case main body at a position facing the opening. The developing roller supports the developer housed in the case main body. The laser printer comprises a photoreceptor that makes contact with the developing roller. An electrostatic latent image is formed on a surface of the photoreceptor. The developer that is supported by the developing roller adheres to the part of the photoreceptor that has the electrostatic latent image. The electrostatic latent image of the photoreceptor thus becomes visible. The developer of the photoreceptor is transferred to the recording medium. As a result, words or images are printed on the recording medium.
An adjustment member for adjusting the thickness of the developer supported on the developing roller is fixed with the case main body of the developing device. The adjustment member extends in the rotation axis direction of the developing roller, and adjusts the thickness of the developer across substantially the entire range of the rotation axis direction of the developing roller. By adjusting the thickness of the developer supported on the developing roller, the developer can be supplied at a constant thickness to the photoreceptor from the developing roller. The density of the developer transferred from the developing roller to the photoreceptor is thus constant.
If the developer housed in the developing device leaks to the exterior, devices disposed at the exterior of the developing device will become soiled. It is necessary to form a developing device from which developer cannot leak. U.S. Pat. No. 6,336,014 utilizes a side seal member such that developer does not leak from end parts in the rotation axis direction of the developing roller The case main body has an area that faces a rotation plane of the developing roller at the end part in the rotation axis direction thereof (below, this area will be termed ‘facing area of the case main body’). The adjustment member extends in the rotation axis direction of the developing roller. As a result, the adjustment member also has an area that faces the rotation plane of the developing roller at the end part in the rotation axis direction thereof (below, this area will be termed ‘facing area of the adjustment member’). The facing area of the case main body and the facing area of the adjustment member are aligned along the rotation direction of the developing roller. In the U.S. Pat. No. 6,336,014, the side seal member has a first elastic member and a second elastic member, the first elastic member being attached to the facing area of the case main body, and the second elastic member being attached to the facing area of the adjustment member. Furthermore, the side seal member has a felt member that passes across both an upper surface (a surface at the developing roller side) of the first elastic member, and an upper surface of the second elastic member. The felt member extends in an integral manner from the upper surface of the first elastic member to the upper surface of the second elastic member. The felt member makes contact with the rotation plane of the developing roller. Therefore, the end part in the rotation axis direction of the developing roller is sealed.